Analysis of cyclic plastic deformation of railroad ballast by DDA

This paper presents an analytical study to elucidate the cyclic plastic deformation of railroad ballast in ballasted railway track under train passage, that is "track deterioration". The simulations of full-scale vertical cyclic loading tests of railroad track regarding a ballast particle as a DDA block were performed, and the applicability of DDA to the cyclic plastic deformation of railroad ballast was discussed. It was found that the cyclic plastic deformation of railroad ballast could be defined as the fabric transformation of particle alignment accompanied by sliding between particles. DDA is useful to trace the movement of particles and to unveil the complex deformation mechanics of granular ballast materials.